epoch1970 wrote: ↑
Sun Mar 22, 2020 11:08 am
I don't know anything about the AoE stuff but in general I think using ethernet in the same way you'd use dedicated audio cabling isn't advantageous.
The beauty of ethernet (or wifi, when it works) + TCP/IP is that it is a transport network, an infrastructure than can serve any purpose.
I read your initial post again. This is how it would be done using LMS, I think:
0 - Have a good local network, ethernet is always the best choice if possible. Flat ethernet cables do exist.
1 - Get a Pi3 or 4. Find a Hat that can manage 4 inputs (or get 4 USB inputs), have these 4 digital streams sent to LMS installed on the Pi. (I think co-location is best for AQ/status feedback, but some people have LMS receive "digital radio" streams from remote inputs.)
2 - Get X more Pis, with analogue out, a DAC Hat, or an amplifier Hat. Typically outputting stereo channels. Install player software on them, typically picorePlayer.
3 - Use the LMS web interface to group players and make groups play one of the 4 sources over the network.
The 1st item is already a bit unusual in the LMS world. More common is the addition of a single input stream, e.g. from a CD player or a turntable; but even this is not a popular use-case. It works, but it isn't end-to-end digital, so less practical/common.
Items 2 and 3 are the way I would do it. If you go to the forums you can find people having something like 6 USB DACs connected to one Pi, running 6 instances of player software. LMS sees 6 independent "zones", never syncs them. Doesn't make any sense to me, but it does exist.
On a good ethernet network, with slimdevices hardware players, you could sync 2 players, have one only render the left channel, the other only the right channel, have the 2 audio speakers centimeters away from each other, and never, ever notice anything wrong.
With the "dedicated software players" we now have, I'm not sure I would try that, but 1 m. away will feel perfect (shoddy network aside.)
This to say that I don't think using a single receiver is a great idea. Using a single sender, LMS, "guarantees" good sync, and I can surely live with that.
If you have a little bit of time, and 1 or more Pis at hand, I would suggest you try picoreplayer. It has a web interface, it serves as a player (its original intent) but it can also host the LMS server (+player if you want.) You can be up and running relatively quickly and get a feel for the server.
Then install a second Pi or install LMS on a VM, a laptop or something, and repurpose the Pi as player. You'll see how it works end-to-end.
To test sync, I would advise to use the same hw/sw combination on all players, so one more Pi would be necessary.
People say that LMS sync is good up to 50 players or something like that. I know a group of 10 is no problem at all, over a non-dedicated network.